197.22/50.53 MAYBE 197.22/50.54 197.22/50.54 Problem: 197.22/50.54 0(0(0(0(x1)))) -> 1(0(1(1(x1)))) 197.22/50.54 0(1(0(1(x1)))) -> 0(0(1(0(x1)))) 197.22/50.54 197.22/50.54 Proof: 197.22/50.54 Open 197.22/50.54 EOF